I would guess that incomplete fermentation or too much priming sugar are the cause. I have had it suggested that it takes longer than 3 weeks for an infection to cause gushers but I don't have direct experience to know.

How did you determine how much priming sugar to use? I started with a kit that contained 5 ounces of sugar for 5 gallons. Then when I started to see how much overcarbonated my beers were I went lower, down to 4.3 ounces. Still overcarbonated so I found a calculator that let me know that for my beers at the temperature I bottled at needed only 3.2 ounces. You should be using a calculator for your beer.

How long has this beer been in the bottle? Sometimes if it hasn't been sitting long enough there will be yeast suspended in the bottle and this yeast can be a nucleation site for the CO2 to come out of suspension. I first learned of how the nucleation sites will cause gushing when I made a spiced ale and the first bottle gushed on opening. Those bottles that sat longer did not gush and the reason the first one did was the particles of spices still suspended in the beer.

How long has this beer been in the bottle? Sometimes if it hasn't been sitting long enough there will be yeast suspended in the bottle and this yeast can be a nucleation site for the CO2 to come out of suspension. I first learned of how the nucleation sites will cause gushing when I made a spiced ale and the first bottle gushed on opening. Those bottles that sat longer did not gush and the reason the first one did was the particles of spices still suspended in the beer.

2 days off of 3 weeks. I understand it could be a number of things. I'm just wondering what the particular symptoms of an infection are because I'm brewing this weekend and bottling the next. So, I'm not sure if I need to go ape-sh!t and clean like I have OCD, throw out hoses, etc. I'll probably just clean everything anyways to be sure.

I had a gusher the other day from a batch that hadn't gushed before. My brother was over and I asked him if anything had "happened" when he got a beer for himself earlier. He responded that one of the big bottles (liters) had fallen out of the fridge and almost hit the floor. I bet that's enough to put a bunch of yeast back into suspension.

I'd have to say they don't always cause bad flavors. My oatmeal stout recently had a gusher infection (whole batch, not over primed or underattenuated) and they tasted fine, if a little thin. Still, it was like old faithful opening one up, so down the drain they went.

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I can't be arsed to keep up this list of what's in the fermenters, but hey, check out the cool brewery I own!

If it's only been 2 days it could be that the C02 hasn't gone into solution, which would give you an overly foamy, flat beer. There's a video on HBT I think Revvu posted about it. Leave the bottle for 2 more weeks (not days, weeks), then try them and see what's what. In the meantime, just in case, place them in a safe, tucked away area (about 70F if you can), and check the caps periodically for bulging. Bulging caps is a sure sign that you either overprimed, didn't let fermentation complete, or have an infection.

The biggest point there is patience. Wait it out, give it a few weeks, and then see. In the meantime you can distract yourself by planning that next batch .

If it's only been 2 days it could be that the C02 hasn't gone into solution, which would give you an overly foamy, flat beer. There's a video on HBT I think Revvu posted about it. Leave the bottle for 2 more weeks (not days, weeks), then try them and see what's what. In the meantime, just in case, place them in a safe, tucked away area (about 70F if you can), and check the caps periodically for bulging. Bulging caps is a sure sign that you either overprimed, didn't let fermentation complete, or have an infection.

The biggest point there is patience. Wait it out, give it a few weeks, and then see. In the meantime you can distract yourself by planning that next batch .

Nah, you misread my post. It was 2 days away from 3 weeks. I'm going to be going nuts trying to figure out what went wrong. It's got to be either in my bottling bucket or auto siphon. I guess I'll be bottling from a carboy the next few times to avoid the potential contaminated bucket. I wish my auto siphon was glass so I could just toss it in the oven!

Nah, you misread my post. It was 2 days away from 3 weeks. I'm going to be going nuts trying to figure out what went wrong. It's got to be either in my bottling bucket or auto siphon. I guess I'll be bottling from a carboy the next few times to avoid the potential contaminated bucket. I wish my auto siphon was glass so I could just toss it in the oven!

Before you go nuts, stick a bottle in the fridge and wait a week. Then see if you are having the same issue.